Acid Blockers Linked to Pneumonia Risk

May 26, 2009 -- An estimated 33,000 deaths a year from hospital-acquired pneumonia may result from the practice of routinely prescribing proton pump inhibitors and other acid-suppressing drugs during hospitalization to patients who don't need them.

Use of acid-reducing drugs was associated with a 30% increased risk for developing pneumonia in a newly reported study.

The drugs are typically given to reduce the risk of stress-related ulcers, which can be life threatening. But they are often prescribed to patients with a very low risk for developing the ulcers, says study researcher Shoshana J. Herzig, MD, of Beth Israel Deaconess Medical Center and Harvard School of Medicine.

Use of proton pump inhibitors (PPIs) has been associated with a slight increase in community-acquired pneumonia risk in several recent studies. But the new research is the first to explore a possible link in hospitalized patients who don't require a ventilator to breathe and are treated outside intensive care units (ICUs).

The study appears in the May 27 issue of TheJournal of the American Medical Association.

"In our study, the risk to the individual patient was small," Herzig tells WebMD. "But because so many people are hospitalized each year, the number of patients involved is not insignificant."

Hospital Patients and PPIs

Previous studies suggest that acid-suppressing medications are prescribed to between 40% and 70% of hospitalized patients in the U.S.

Herzig and colleagues reviewed the medical records of almost 64,000 non-ventilated, non-ICU adult patients hospitalized and treated at Beth Israel Deaconess between 2004 and 2007 and found that 52% were prescribed acid-reducing drugs.

Of these, 83% were prescribed proton pump inhibitors and 23% received another class of acid-suppressives known as H2 blockers. Examples of PPIs include Aciphex, Nexium, Prevacid, Prilosec, and Protonix. H2 blockers include Axid, Pepcid, Tagamet, and Zantac.

In nine out of 10 cases the drugs were prescribed within 48 hours of admission.

The review of patient records revealed that:

3.5% of patients developed hospital-acquired pneumonia.

After adjusting for other risk factors for pneumonia, use of acid-suppression drugs was associated with a 30% increased risk for developing hospital-acquired pneumonia.

The association was statistically significant for proton pump inhibitors, but not for H2 blockers.